mliller



fNoMoael.) A. E. MULLER.

Esoapement.

No. 231,839. Patented Aug. 31,1880e N4 PETERS, PHOTO-UTHOGHAPHiR.wASNlNGTON. D C.

'UNITEU STATES PATENT Omtrente AUGUST E. MLLER, OF VIENNA, AUSTRIA.

ESCAPEM ENT.

Application filed March 10, 1380.

lated August 31, 1880,

(No model.) Patented in Belgium December 1T, 1879.

To uit whom it may concern:

Be it known that I, AUGUST ERNST ML- LER, a resident of Vienna, inAustria, in the Province of Lower Austria, and a citizen of Germany,have invented certain new and useful Improvements in Time-Keepers calledNormal Ohronometer-Motions577 and I do hereby declare that the followingis a full, clear, and exact description of the invention, which willenable others skilled in the art to which it appertains to make and usethe same, reference being had to the accompanying drawings, and to theletters of reference marked thereon, which form a partof thisspecification.

This invention relates to an escapement for chronometer-movements; andit consists in a non-expansive balance consisting of weights orrim-segments supported 011 the ends of wooden arms, said arms beingrendered impervious to atmosphericiniiuences and changes of temperatureby being dried and saturated with varnish or equivalent material.

It also consists in the combination, with the non-expansible balancesupporting the end weights or rim-segments upon its woodenvarnish-coated arms, of a spring having one end ii'xed to the shaft ofthe arbor on which the balance is mounted and its other end cou nectedwith the frame supporting the time mechanism, the impulse mechanism, anda spring' for imparting motion to the balance, and a lever swinging on apivot and actuated by said balance, the said pivotalso carrying thedetent mechanism, substantially as set forth.

Figure l is a plan view of the parts of a chronometer or time-piececontaining my invention. Fig. 2 is a detached view of the same, partlyin section. Fig. 3 is a side view of the same. Fig. 4 is au invertedplan view, showing the impulse-spring and its regulators.

Similar letters indicate corresponding parts.

In the example shown in the drawings the letter A designates thescape-wheel, which is urged by the motor to revolve in the direction ofthe arrow-head l.

B B is the balance. This balance consists of arms e e, of somenon-expansive material-as, by preference, wood, boxwood being the mostsuitable. These wooden arms are rendered impervious to atmosphericinliuences and changes of temperature in the following manner: The

roughly-finished wooden arms are laid wire-nettings suspended in a boxor apartment. The temperature in this box is kept,by a spirit-lamp orother suitable lneans, at a temperature of from 1G00 to 1800 Reaumur, asindicated by a thermometer which is to be connected therewith. Afterbeing exposed to this temperature about twelve hours and dried, thewooden arms, while still hot, are immersed in copal-varnish, whereby thepores of the wood, after a few hours, become saturated with the same.These arms are then freed from the varnish adhering to the surface, andagain introduced into the dryine apparatus, and exposed for abouttwenty-tour hours to a heat of from 600 to 1000 Reaumur. These arms maynow be exposed to considerable variations in temperature without theirlength being altered thereby, nor are they sensible to hygroscopicalintluences. To these arms e e are fastened the rim-segments fj', ot'brass or any other heavy metal or substance. In chronometers thesesegments j'j'will be provided with mean-time screws for regulating themoment of inertia ot' the balance.

In ordinary time-pieces the hair-spring G of the balance may be variedin length, as is now done in watches, whereby the angular velocity ofthe balance can be varied.

To the arbor of the balance is attached the main pallet b, carrying thelifting-pallet c, both oscillating with the balance. When swinging inthe direction of the arrow-head 2 the liftingpallet c passes in betweenthe two prongs o o of the forked end ofthe detent-leyeron, carrying italong'. The center prong of the lever m is raised,al1owing thelifting-pallet cto pass underneath. This center prong engages a notch,t', in a raised portion ofthe main pallet b. The lever m is thus causedto swing about its pivot a', and its inner end to pass' away from thestop-pin p, rising from one of the frame-plates of the mechanism. Thedetent consists in this case ofa sector, 7a k', of rubyor steel,connected with the lever m. As the inner end of this lever in is causedto swing away from the pin 17, the tooth u of the scape-wheel is freedfrom the end k of the detent, andthe wheel springs forward until thetooth u abuts against theinner side of the end It' of the detent. Bythis movement ot' the scape-wheel A the arm s of upon suitable IOO-turns in the frame of the machine.

.the same asits effect on the spring the impulse mechanism is freed fromits contact with the tooth u2, and the action of its spring tswings theimpulse mechanism in the direction of the arrow 3.

The motions of the balance and the impulse mechanism are so timed thatwhen the impulse mechanism swings in the direction of the arrow 3 thearm s' of the same strikes against the pallet or stud a on the mainpallet I), giv-` ing the balance B B a push in the direction of thearrow 2. The arm s consists of a thin elastic piece of metal or steel.The action of the springt swings theimpulse mechanism in the directionof arrow 3 until thc arm s" abuts against the stop-pin z, rising from aframeplate. The arbor r of the impulse mechanism The bal ance B nowmoves back in the direction opposed to the arrow 2, under the influenceof its spring Gr. The inner end of the arm m is thus carried back to itsoriginal position against the stop-pin p. The tooth a of the scape-wheelis thus freed from its contact with the end k of the detent, and thewheel springs t'crward until the tooth a@ abuts against the end 7c ofthe detent. The impulse mechanism is thereby carried back to itsoriginal position by the tooth a engaging the arm s, and the action ofthe several parts is repeated, as before.

In place of a detent of the form shown in Fig. 2, an anchor may besubstituted, the action of whose pallets on the teeth of the scapewheelA will be analogous to the action ofthe detent 7c 7".

As is well-known, when the time-piece is exposed to a rise oftemperature the hair-spring Gr of the balance is lengthened, it-s actionon the balance B B weakened. Consequently the angular velocity of thebalance is diminished and the mechanism goes too slow. The reverse takesplace on a fall of temperature, and too great rapidity7 is the result.But the action of the temperature on the spring t is precisely G.Consequently, on a rise of temperature, when the spring t is lengthenedthe impulses of the arm s on the pallet a are weakened, and the numberot' oscillations of the balance B remains uniform for equal periods oftime. ()n a fall of temperature the impulses are stronger and theresistance of the spring G is greater. Thus it will be seen that bythe'arrangement of the two springs G t, with appropriate mechanism, anychange in one spring, by reason of changes of temperature or otheratmospheric influences, is exactly compensated by the change from thesame causes in the other spring, whereby great accuracy of the mechanismis obtained.

In order to tighten the spring t a disk, TT, is provided, which is heldin place by the slanting edge of a circular plate, c fv, screwed orotherwise fastened tothe base-plate C C. .About this plate c e the diskT T can be turned by the nose W. The plate T carries a stud, t', towhich one end of the spring t is fastened, so that by turning the plateT in the proper direction the spring t is subjected to greater or lesstension. A regulating-hand, D, working on the ordinary principle, isfurther provided for adjusting the action of the spring t.

The edges of the teeth of the scape-wheel are cut wedge-shaped, asshown, and the end of the. arm s. as also the faces ot' the detent k7c', are so formcdfzthat the only resistance to be overcome is theslight friction of these parts against each other, so that as littleforce as possible is expended, contributing largely to the durability ofthe instrument.

What I claim as new, and desire to secure by Letters Patent, is

l. In an escapement for chronometer-movements, a non-expansive balanceconsisting of weights or rim-segments f,supported on wooden arms c, saidarms being rendered impervious to atmospheric intluences and changes oftemperature by being dried and saturated with varnish or equivalentmaterial, substantially as set forth.

2. Thecombination, with the non-expansible balance B, supporting theweights or rim-segments j upon its wooden varnish-coated arms e, ot' thespring G, having one end fixed to the shaft of the arbor on which thebalance is mounted and its other end connected with the frame supportingthe time mechanism, the impulse mechanism, and spring F, for impartingmotion to thebalance, and the lever m, swingingon a pivot, af, andactuated by said balance, said pivot a also carrying the detentmechanism, substantially as described.

In testimony that I claim the foregoing as my own I affix my signaturein presence of two witnesses.

' AUG. ERNST MLLER.

Witnesses:

JOHANN COLRAK, ROBERT B. J EN'rzscH.

IOO

